1. Why don’t we go to the park? (HOW ABOUT)
=> how about going to the park?

2. I want you to do your homework carefully. (RATHER)
=> I would rather you did your homework carefully 

3. I’m excited about planting flowers. (KEEN)
=> I’m keen on planting flowers.

4. I haven’t gone to the cinema before. (FIRST)
=> this is the first time i have gone  to the cinema